Quartile Of Calcium Research Articles

The association of admission ionized calcium with outcomes of thrombolysed patients with anterior circulation ischemic stroke.

The relationship between ionized calcium and prognosis of ischemic stroke is controversial. We aim to determine the relationship of admission ionized calcium levels with acute ischemic stroke (AIS) after intravenous thrombolysis (IVT). Consecutive anterior circulation AIS patients treated with recombinant tissue plasminogen activator (rt-PA) were retrospectively enrolled. According to ionized calcium quartiles, the patients were divided into four groups and clinical data were analyzed between groups. Ionized calcium was entered into logistic regression analysis in two models, separately: model 1, calcium as a continuous variable (per 1-mmol/L increase), and model 2, calcium as the four-categorized variable (being collapsed into quartiles: Q1-Q4). Early neurologic improvement (ENI) was defined as improvement of four or more points at 24h after intravenous rt-PA, while long-term good outcome as the modified Rankin Scale (mRS) 0-1 at 90 days. A total of 546 patients met the study criteria (mean age was 63.51±11.26 years and 365 [66.8%] were men). The median admission National Institute of Health Stroke Scale was 9 (range 4 to 15). When not adjusted, in model 1: ionized calcium was related to good outcome (odds ratio [OR] 69.061, 95%CI: 1.638-2911.111, p=0.027), but not ENI (OR 14.097, 95%CI: 0.133-1492.596, p=0.266); in model 2: compared with Q4, while good outcome was less common in Q1 (OR 0.623, 95%CI: 0.388-0.999, p=0.049). After adjusting for confounding factors, calcium in Q2 (OR 0.502, 95%CI: 0.253-0.997, p=0.049) was independently associated with ENI, but no matter as a continuous variable or categorized variable, ionized calcium displayed no association with a good outcome. The current results found that ionized calcium might be associated with early neurological improvement, but had no association with 3 months' outcome in anterior circulation AIS patients after IVT.

Association of admission serum calcium level with left ventricular dysfunction in patients with acute coronary syndrome.

The relationship between serum calcium and left ventricular function in patients with acute coronary syndrome (ACS) has not been explored. Our aim was to investigate the correlation of admission serum calcium with left ventricular dysfunction in ACS patients. In this cross-sectional study, 658 ACS patients who were admitted in the Department of Cardiovascular Disease from June 1st, 2019 to December 31st, 2019 were enrolled in the present study. Serum calcium and B-type natriuretic peptide (BNP) were measured at admission. Left ventricular ejection fraction (LVEF) was assessed using echocardiography. The correlation between admission serum calcium and left ventricular dysfunction was analyzed. When stratified by serum calcium quartiles calculated from all patients, patients with lower serum calcium quartile showed a markedly higher BNP and lower LVEF (P < 0.05). Patients with LVEF ≤ 50% showed a significantly lower serum calcium and higher BNP compared to those with LVEF> 50% (P < 0.05). Admission serum calcium was positively correlated with LVEF (P < 0.01) but negatively correlated with BNP (P < 0.01). Multivariate logistic regression analysis showed that lower serum calcium (adjusted OR: 0.720, 95% CI: 0.519-0.997, P = 0.048) was independently associated with BNP ≥ 300 pg/ml in ACS patients. Using LVEF as a dependent variable, no significant correlation between low serum calcium and left ventricular systolic dysfunction was found in ACS patients. In patients with ACS, admission serum calcium was positively correlated with LVEF and negatively with BNP. Lower admission serum calcium was an independent risk factor for elevated BNP.

Association of dietary calcium, magnesium, sodium, and potassium intake and hypertension: a study on an 8-year dietary intake data from the National Health and Nutrition Examination Survey.

BACKGROUND/OBJECTIVESThere has been an increased interest in determining calcium magnesium, sodium, and potassium's distinct effects on hypertension over the past decade, yet they simultaneously regulate blood pressure. We aimed at examining the association of dietary calcium, magnesium, sodium, and potassium independently and jointly with hypertension using National Health and Nutrition Examination Survey data from 2007 to 2014.MATERIALS/METHODSThe associations were examined on a large cross-sectional study involving 16684 US adults aged>20 years, using multivariate analyses with logistical models.RESULTSSodium and calcium quartiles assessed alone were not associated with hypertension. Potassium was negatively associated with hypertension in the highest quartile, 0.64 (95% confidence interval [CI], 0.48–0.87). When jointly assessed using the high and low cut-off points, low sodium and corresponding high calcium, magnesium, and potassium intake somewhat reduced the odds of hypertension 0.39 (95% CI, 0.20–0.76). The sodium-to-potassium ratio was positively associated with hypertension in the highest quartile1.50 (95% CI, 1.11–2.02). When potassium was adjusted for sodium intake and sodium-to-potassium ratio assessed among women, increased odds of hypertension were reported in the highest quartile as 2.02 (95% CI, 1.18–3.34) and 1.69 (95% CI, 1.12–2.57), respectively. The association of combined minerals on hypertension using dietary goals established that men meeting the reference intakes for calcium and exceeding for magnesium had reduced odds of hypertension 0.51 (95% CI, 0.30–0.89). Women exceeding the recommendations for both calcium and magnesium had the lower reduced odds of 0.30 (95% CI, 0.10–0.69).CONCLUSIONSOur results suggest that the studied minerals' association on hypertension is stronger when jointly assessed, mostly after gender stratification. As compared to men, women increased their risk of hypertension even with a low sodium intake. Women would also reasonably reduce their risk of developing hypertension by increasing calcium and magnesium intake. In comparison, men would somewhat be protected from developing hypertension with calcium intake meeting the dietary goals and magnesium exceeding the nutritional goals.

Serum calcium and long-term outcome after ischemic stroke: Results from the China National stroke registry III

Background and aimsSerum calcium abnormality is associated with adverse cardiovascular outcomes, but the effects of serum calcium level on stroke outcomes remain unknown. We aimed to assess the relationship between serum calcium level and 1-year outcomes in patients with acute ischemic stroke and transient ischemic attack. MethodsWe included 9375 stroke patients from the China National Stroke Registry III for analysis. Participants were divided into 4 groups according to albumin corrected-calcium quartiles. Composite end point comprised recurrent stroke, myocardial infarction, other ischemic vascular events, and all-cause mortality. Multivariable Cox or logistic regression was used to evaluate the independent association of albumin corrected-calcium with all-cause mortality, recurrent stroke, composite end point, and poor functional outcome (modified Rankin Scale score ≥3). ResultsCompared with the lowest calcium quartile (<2.16 mmol/L), the adjusted hazard ratio (95% CI) of the top quartile (≥2.31 mmol/L) was 1.56 (1.11–2.18) for all-cause mortality, 1.06 (0.87–1.28) for recurrent stroke and 1.08 (0.90–1.01) for composite end point, and the adjusted odds ratio for poor functional outcome was 1.18 (0.96–1.44). The addition of serum calcium to conventional risk factors improved risk prediction of all-cause mortality, leading to a small but significant increase in C-statistics and reclassification with non-significant integrated discrimination improvement (C-statistics, p = 0.02; net reclassification index 11.8%, p = 0.038; integrated discrimination improvement 0.08%, p = 0.42). ConclusionsHigh serum calcium levels at baseline were associated with all-cause mortality at 1-year after ischemic stroke, suggesting that serum calcium may be a potential prognostic biomarker and therapeutic target for ischemic stroke.

Low serum calcium is associated with higher long-term mortality in myocardial infarction patients from a population-based registry

Calcium plays an essential role in physiology of the cardiovascular system. Aberrations from normal serum calcium levels are known to be associated with several cardiovascular diseases. Its possible role as a predictor for long-term mortality after acute myocardial infarction (AMI) is still uncertain. In this study, a total of 3732 patients (aged 25–74 years) with incident AMI surviving at least 28 days after AMI was included. The median follow-up time was 6.0 years. Admission total serum calcium levels were divided into quartiles. The Kaplan–Meier-Curve suggested a division of the follow up time in two different time periods. So, Cox regression models were calculated to assess association between admission serum calcium levels and all-cause long-term mortality with two observation periods: 28–2500 days and > 2500 days. The final model was adjusted for various comorbidities, clinical characteristics, in-hospital treatment and medication. The third quartile (normal-high Calcium levels) served as the reference group. The fully adjusted Cox-regression model shows significantly higher mortality risk for low serum calcium (quartile 1) within the timeframe 28–2500 days after the event (OR 1.53 [1.19–1.98]). The other groups did not differ significantly from each other. In the later observation period (from 2500 days until death or censoring) no more significant differences were seen between the four calcium quartiles. In summary, low serum calcium is an independent predictor of adverse outcome in the first 2500 days (about 7 years) after AMI. On later points in time this effect attenuates, so that no more significant differences can be observed.

Low Zinc, Copper, and Manganese Intake is Associated with Depression and Anxiety Symptoms in the Japanese Working Population: Findings from the Eating Habit and Well-Being Study.

Epidemiological studies have suggested that there is an association between diet and mental health. The aim of this study was to investigate the association between the intake of six minerals and mental disorders in a cross-sectional study. We used data from the Eating Habit and Well-being study in Japanese workers. Kessler’s six-item psychological distress scale was used to detect mental disorders, with a cut-off score of 12/13, and a validated food frequency questionnaire was used to estimate dietary mineral intake. A total of 2089 participants with no history of depression were included. The prevalence of mental disorders was 6.9%. The lowest quartiles of zinc, copper, and manganese intakes were associated with mental disorders, whereas the lowest quartiles of calcium, magnesium, and iron intake were not associated with mental disorders. Combination analysis of high (≥median) or low (<median) intake of zinc, copper, and manganese showed that low zinc and low copper intake, even with low or high manganese intake (odds ratio (OR), 2.71, 95% confidence interval (CI), 1.29–5.73, and OR, 3.06, 95% CI, 1.41–6.61, respectively) showed a higher OR than that of high zinc, high copper, and high manganese intake. Further studies are required to investigate the impact of dietary mineral intake on mental health.

SUN-053 Gender Disparity In Association Between Serum Total Calcium And Blood Pressure In A Normocalcemic High Salt Diet Population.

Calcium metabolism has been shown to be associated with blood pressure, however, the results from gender subgroup analysis is conflicting. Some studies have shown strong correlation in women while other studies have shown weaker associations in women. Hence, the purpose of this epidemiology study is to evaluate the association of serum total calcium levels with blood pressure based on gender. This is a secondary analysis of epidemiology data from the Northeast China Rural Cardiovascular Health Study conducted 2012-2013. Resting blood pressure was measured 3 times in each participant using a standardized electric sphygmomanometer after sitting for 5 min. Men and non-pregnant women ≥18 years old, normocalcemic (2.25-2.58 mmol/L) [Diagnostics, 9th ed. People's Medical Publishing, China], and no prior history of hypertension or anti-hypertension medication were included. Serum calcium levels were stratified into quartiles (i.e., Q1: 2.25-2.33 mmol/L, Q2: 2.33-2.41, Q3: 2.41-2.50, Q4: 2.50-2.58 mmol/L), and hypertension was defined as mean systolic BP ≥140mmHg and/or mean diastolic BP ≥90mmHg. This study population has been previously shown to have high salt intake (9.7 g/d) [Li et al. J Am Soc Hypertens 9:358]. A total of 6550 normocalcemic participants met the inclusion criteria, of whom 51% were women and 39% were hypertensive. The mean serum calcium level was slightly higher in men than in women (2.38 ± 0.08 vs. 2.37 ±0.08; p=0.007) More men were hypertensive than women (42.6% vs. 35.1%; p<0.001). In the serum calcium quartiles, 34% (805/2401) normocalcemic participants in the lowest quartile Q1 were hypertensive, 38% (777/2037) in Q2, 44% (649/1470) in Q3, and 48% (310/642) in Q4. For men, the odds of hypertension increases as serum calcium quartile increases: the odds of hypertension in Q3 is 39% (95% CI, 1.151-1.673) higher compared to Q1, and in Q4 is 67% (95% CI, 1.321-2.160) higher. Similarly, in non-pregnant women, the odds of hypertension increases through the quartiles when compared to Q1: Q2 is 31% (95% CI, 1.095-1.556) higher, Q3 is 75% (1.448-2.121) higher, and Q4 is 99% (95% CI, 1.545-2.573) higher. Even though the odds of hypertension were consistently higher in women than in men in all serum calcium quartiles, there was no statistical difference in the odds ratio. In linear regression, the serum calcium level is a stronger predictor of systolic BP in women than in men (0.175 vs. 0.110; p=0.008), however the association with diastolic BP tends to be stronger in men than in women (0.070 vs. 0.063; p=0.74). In conclusion, in normocalcemic participants without a history of hypertension, the odds of having high blood pressure increases as serum calcium levels increases even within the normal range. In this high salt diet population, women trends to having higher odds of hypertension with a stronger association of systolic BP to serum total calcium levels.

Association of abnormal serum electrolyte levels with hypertension in a population with high salt intake.

The present epidemiological study aimed to evaluate the association of serum electrolyte levels with hypertension in a population with a high-salt diet. Secondary analysis of epidemiology data from the Northeast China Rural Cardiovascular Health Study conducted in 2012-2013. Blood pressure and hypertension status were analysed for association with serum sodium, potassium, chloride, total calcium, phosphate and magnesium levels using regression models. High-salt diet, rural China.ParticipantsAdult residents in Liaoning, China. In total 10 555 participants were included, of whom 3287 had incident hypertension (IH) and 1655 had previously diagnosed hypertension (PDH). Fifty-six per cent of participants had electrolyte disturbance. Sixty-two per cent of hypercalcaemic participants had hypertension, followed by hypokalaemia (56 %) and hypernatraemia (54 %). Only hypercalcaemia showed significant associations with both IH (OR=1·70) and PDH (OR=2·25). Highest serum calcium quartile had higher odds of IH (OR=1·58) and PDH (OR=1·64) than the lowest quartile. Serum sodium had no significant correlation with hypertension. Serum potassium had a U-shaped trend with PDH. Highest chloride quartile had lower odds of PDH than the lowest chloride quartile (OR=0·65). Highest phosphate quartile was only associated with lower odds of IH (OR=0·75), and the higher magnesium group had significantly lower odds of IH (OR=0·86) and PDH (OR=0·77). We have shown the association of serum calcium, magnesium and chloride levels with IH and/or PDH. In the clinical setting, patients with IH may have concurrent electrolyte disturbances, such as hypercalcaemia, that may indicate other underlying aetiologies.

Serum Calcium Concentrations, Chronic Inflammation and Glucose Metabolism: A Cross-Sectional Analysis in the Andhra Pradesh Children and Parents Study (APCaPS)

BackgroundEvidence suggests a role for elevated serum calcium in dysregulated glucose metabolism, linked through low-level chronic inflammation. ObjectivesWe investigated the association of elevated serum calcium concentrations (corrected for albumin) with markers of dysregulated glucose metabolism and type II diabetes and tested if these associations were accounted for by chronic inflammation in a rural Indian population. MethodsA cross-sectional analysis of participants aged 40–84 y from the Andhra Pradesh Children and Parents Study (APCaPS; n = 2699, 52.2% women) was conducted. Comprehensive information on household, sociodemographic, and lifestyle factors; medical and family history; physical measurements; blood measurements including fasting plasma glucose (FPG), fasting insulin (FI), serum calcium, albumin, phosphorous, vitamin D (in a subset), and creatinine were analyzed. Additionally, in a random sample of healthy participants (n = 1000), inflammatory biomarkers (interleukins 6 and 18, soluble intercellular adhesion molecule 1, adiponectin, and high-sensitivity C-reactive protein) were measured and an inflammatory score (IScore) calculated. ResultsAfter adjustments for sociodemographics, lifestyle factors, and anthropometry the highest calcium quartile (Q4 compared with Q1) was associated with FI (β = 1.4 µU/ml; 95% CI: 1.2, 1.5 µU/ml; P-trend < 0.001), the homeostasis model assessment for insulin resistance (HOMA-IR) (β = 1.4; 95% CI: 1.2, 1.5; P-trend < 0.001), and was modestly associated with FPG (β = 2.1 mg/dL; 95% CI: −0.9, 5.2 mg/dL; P-trend = 0.058) and prevalent type II diabetes (OR = 1.6; 95% CI: 1.0, 2.6; P-trend= 0.020). In the healthy subgroup, the association of the highest calcium quartile was similar for FI and HOMA-IR. Additional adjustment with IScore did not alter the associations. Further, in a subset, all these associations were independent of endogenous regulators of calcium metabolism (serum vitamin D, phosphorus, and creatinine). Independently, after accounting for potential confounders, the highest IScore quartile (Q4 compared with Q1) was positively associated with FPG, FI, HOMA-IR, and prevalent prediabetes, and also with serum calcium concentrations in men. ConclusionsElevated serum calcium was positively associated with markers of dysregulated glucose metabolism and prevalent type II diabetes in a rural Indian population. Chronic inflammation did not mediate this association but was independently associated with markers of dysregulated glucose metabolism. Inflammation might be responsible for elevated serum calcium concentrations in men.

Association of pregnancy hypocalcemia and neonatal growth indices.

Introduction: Hypocalcemia is a common condition in pregnancy. Approximately 20-30 g maternal calcium is actively transferred to the fetus during pregnancy for fetal skeletal mineralization. The aim of this study was to determine the association of pregnancy hypocalcemia with neonatal growth indices. Methods: This cohort study was conducted on 112 pregnant women with the gestational age of 22-26 weeks in 2016. Calcium, albumin, 25(OH)D, and urinary calcium/creatinine ratio were measured for all participants. Hypocalcemia was defined as corrected serum calcium level of 0.05). Furthermore, neonatal growth indices were not significantly different in the maternal calcium quartiles. The two groups showed no significant difference in terms of the adjusted mean of neonatal growth indices (P>0.05). Conclusion: According to the findings of the present study, hypocalcemia was a prevalent condition in pregnancy; however, this condition exerted no adverse effects on neonatal growth indices.

Low Calcium Intake in Midpregnancy Is Associated with Hypertension Development within 10 Years after Pregnancy: The Norwegian Mother and Child Cohort Study

Background: Low dietary calcium intake may be a risk factor for hypertension, but studies conflict.Objective: We evaluated the ability to predict hypertension within 10 y after delivery based on calcium intake during midpregnancy.Methods: The Norwegian Mother and Child Cohort Study of women delivering in 2004-2009 was linked to the Norwegian Prescription Database (2004-2013) to ascertain antihypertensive medication usage >90 d after delivery. Women with hypertension before pregnancy were excluded, leaving 60,027 mothers for analyses. Age and energy-adjusted cubic splines evaluated dose-response curves, and Cox proportional hazard analyses evaluated HR and 95% CIs by calcium quartiles adjusting for 7 covariates. Analyses were stratified by gestational hypertension and by sodium-to-potassium intake ratio (<0.76 compared with ≥0.76).Results: Participants had a mean ± SD age of 30.5 ± 4.6 y, a body mass index (in kg/m2) of 24.0 ± 4.3 before pregnancy, and a mean follow-up duration of 7.1 ± 1.6 y. Cubic spline graphs identified a threshold effect of low calcium intake only within the range of dietary inadequacy related to increased risk. The lowest calcium quartile (≤738 mg/d; median: 588 mg/d), relative to the highest quartile (≥1254 mg/d), had an HR for hypertension of 1.34 (95% CI: 1.05, 1.70) among women who were normotensive during pregnancy, and an HR of 1.62 (95% CI: 1.14, 2.35) among women who had gestational hypertension, after adjusting for covariates. Women with gestational hypertension, who were in the lowest quartile of calcium intake, and who had a high sodium-to-potassium intake ratio had a risk of hypertension more than double that of their counterparts with a calcium intake in the highest quartile. Results were attenuated by adjusting for covariates (HR: 1.92; 95% CI: 1.09, 3.39).Conclusions: The results suggest that low dietary calcium intake may be a risk factor or risk marker for the development of hypertension, particularly for women with a history of gestational hypertension.

Associations between serum levels of calcium, parathyroid hormone and future risk of venous thromboembolism: the Tromsø study.

The relationship between serum levels of calcium, parathyroid hormone (PTH) and risk of venous thromboembolism (VTE) has not been addressed in population-based cohorts. We investigated the associations between serum levels of calcium and PTH, with future risk of VTE in a general adult population. Population-based cohort. A total of 27 712 subjects (25-87 years) who participated in Tromsø 4 (1994-1995) and Tromsø 5 (2001-2002) surveys were included in the study, and total calcium and PTH were measured in 27 685 and 8547 subjects respectively. Incident VTE was recorded through December 31, 2012. Cox-regression models with calcium and PTH as time-varying exposures were used to calculate hazard ratios (HR) of VTE by quartiles of calcium and PTH. Quartiles of calcium and PTH were also combined to assess the effect of discordants of both PTH and calcium (e.g. highest and lowest quartiles of both calcium and PTH) on VTE risk using the middle two quartiles as reference. There were 712 VTEs during 15.0 years of median follow-up. Serum levels of calcium and PTH were not associated with risk of VTE. However, subjects with discordant high serum levels of both calcium and PTH (calcium ≥2.45 mmol/L and PTH ≥4.0 pmol/L) had increased risk of VTE compared to those in subjects with normal calcium and PTH (multivariable HR: 1.78, 95% CI: 1.12-2.84). Serum levels of calcium and PTH separately were not associated with future risk of VTE, but subjects with high levels of both calcium and PTH had increased risk of VTE compared to those in subjects with normal levels.

Dietary factors and fibroblast growth factor-23 levels in young adults with African ancestry.

Fibroblast growth factor-23 (FGF23), a phosphaturic hormone secreted mainly by osteocytes, maintains serum phosphate levels within a tight range by promoting phosphaturia. Previous studies have mainly focused on the link between FGF23 levels and dietary intake of phosphate, but other dietary factors may also influence FGF23 levels. This cross-sectional study pooled three populations of young adults with African ancestry (452 in Chicago, IL, USA; 477 in Victoria, Seychelles; and 482 in Kumasi, Ghana) with estimated glomerular filtration rate >80ml/min/1.73m2 to examine the association of dietary factors based on two 24-h recalls with FGF23 levels measured using a C-terminal assay. Linear regression was used to examine the association between log-transformed FGF23 levels and quartiles of calorie-adjusted dietary factors with adjustment for covariates. In the pooled sample of 1411 study participants, the mean age was 35.2 (6.2) years and 45.3% were male. Median plasma C-terminal FGF23 values in relative units (RU)/ml were 59.5 [interquartile range (IQR) 44.1, 85.3] in the USA, 43.2 (IQR 33.1, 57.9) in Seychelles, and 34.0 (IQR 25.2, 50.4) in Ghana. With adjustment for covariates, increasing quartiles of calcium and animal protein and decreasing quartiles of vegetable protein, fiber, and magnesium intake were associated with significantly higher FGF23 levels compared to the lowest quartile. After further adjustment for dietary factors, significant trends in FGF23 levels were noted only for quartiles of calcium, fiber, and magnesium intake (P<0.001). Dietary factors other than phosphate are associated with FGF23 levels in young adults.

Association of serum calcium and heart failure with preserved ejection fraction in patients with type 2 diabetes.

BackgroundType 2 diabetes mellitus (T2DM) is a recognized trigger factor for heart failure with preserved ejection fraction (HFpEF). Recent studies show that higher serum calcium level is associated with greater risk of both T2DM and heart failure. We speculate that increased serum calcium is related to HFpEF prevalence in patients with T2DM.MethodsIn this cross-sectional echocardiographic study, 807 normocalcemia and normophosphatemia patients with T2DM participated, of whom 106 had HFpEF. Multinomial logistic regression was carried out to determine the variables associated with HFpEF. The associations between serum calcium and metabolic parameters, as well as the rate of HFpEF were examined using bivariate linear correlation and binary logistic regression, respectively. The predictive performance of serum calcium for HFpEF was evaluated using the area under the receiver operating characteristic curve (AUC).ResultsPatients with HFpEF have significantly higher serum calcium than those without HFpEF. Serum calcium was positively associated with total cholesterol, triglycerides, low-density lipoprotein cholesterol, serum uric acid, HOMA-IR and fasting plasma glucose. Compared with patients in the lowest serum calcium quartile, the odds ratio (OR) for HFpEF in patients in the highest quartile was 2.331 (95 % CI 1.088–4.994, p = 0.029). When calcium was analyzed as a continuous variable, per 1 mg/dL increase, the OR (95 % CI) for HFpEF was [2.712 (1.471–5.002), p = 0.001]. Serum calcium can predict HFpEF [AUC = 0.673, 95 % CI (0.620–0.726), p < 0.001].ConclusionsAn increase in serum calcium level is associated with an increased risk of HFpEF in patients with T2DM.

Cross-sectional analysis of serum calcium levels for associations with left ventricular hypertrophy in normocalcemia individuals with type 2 diabetes.

BackgroundLeft ventricular hypertrophy (LVH) is prevalent in patients with type 2 diabetes mellitus (T2DM). Recent studies show that an increase in albumin-adjusted serum calcium level is associated with an elevated risk of T2DM. We speculate that increased serum calcium levels in T2DM patients are related to LVH prevalence.MethodsIn this echocardiographic study, 833 normocalcemia and normophosphatemia patients with T2DM were enrolled. The associations between serum calcium and metabolic parameters, left ventricular mass index (LVMI), as well as the rate of LVH were examined using bivariate linear correlation, multivariate linear regression and logistic regression, respectively. The predictive performance of serum calcium for LVH was evaluated using the area under the receiver operating characteristic curve (AUC).ResultsPatients with LVH have significantly higher serum calcium than those without LVH. Serum calcium was positively associated with total cholesterol, triglycerides, low-density lipoprotein cholesterol, serum uric acid, HOMA-IR and fasting plasma glucose. Multivariate linear regression analysis demonstrated that serum calcium was independently associated with LVMI (p < 0.001). In comparison with patients in the lowest serum calcium quartile, the odds ratio (OR) for LVH in patients in the highest quartile was 2.909 (95% CI 1.792-4.720; p < 0.001). When serum calcium was analyzed as a continuous variable, per 1 mg/dl increase, the OR (95% CI) for LVH was [2.400 (1.552-3.713); p < 0.001]. Serum calcium can predict LVH (AUC = 0.617; 95% CI (0.577-0.656); p < 0.001).ConclusionsAlbumin-adjusted serum calcium is associated with an increased risk of LVH in patients with T2DM.

Low serum calcium is associated with poor renal outcomes in chronic kidney disease stages 3–4 patients

BackgroundMineral disorders are associated with adverse renal outcomes in chronic kidney disease (CKD) patients. Previous studies have associated hypercalcemia and hypocalcemia with mortality; however, the association between serum calcium and renal outcome is not well-described. Whether adding calcium besides phosphorus or in the form of calcium-phosphorus (Ca × P) product into the model of survival analysis could improve the prediction of renal outcomes is not known.MethodsA prospective cohort of 2144 outpatients with CKD stages 3–4 was evaluated. Cox proportional hazard analysis was performed according to calcium quartiles.ResultsThe mean calcium level was 9.2 ± 0.7 mg/dL. Low serum calcium (<9.0 mg/dL) was associated with increased risk of requiring renal replacement therapy (RRT) (hazards ratio [HR]:2.12 (95% CI: 1.49–3.02, P <0.05) and rapid renal function progression (odds ratio [OR]: 1.65 (95% CI: 1.19–2.27, P <0.05) compared with high serum calcium (>9.8 mg/dL). Adding calcium into the survival model increased the integrated discrimination improvement by 0.80% (0.12% – 1.91%) while calcium-phosphorus product did not improve risk prediction.The combination of high serum phosphorus (>4.2 mg/dL) and low serum calcium (<9.1 mg/dL) was associated with the highest risk of RRT (HR:2.31 (95% CI: 1.45–3.67, P < 0.05).ConclusionLow serum calcium is associated with increased risk of RRT and rapid renal function progression in CKD stage 3–4 patients. The integration of serum calcium and phosphorus, but not calcium-phosphorus product should be considered in a predictive model of renal outcome.Electronic supplementary materialThe online version of this article (doi:10.1186/1471-2369-15-183) contains supplementary material, which is available to authorized users.

Postmenopausal women with carotid atherosclerosis: Potential role of the serum calcium levels

Background and aimStudies on the association between serum calcium levels and cardiovascular diseases suggested a causative role for hypercalcemia but other studies showed that even serum calcium levels within normal range could be involved in atherosclerosis. However, while dietary calcium intake does not seem to be related to adverse cardiovascular effects, the association between calcium supplementation and the cardiovascular events has not been fully proven. Our aim was to determine the relation between serum calcium levels, within normal range, and the presence of carotid atherosclerosis in a population in whom investigations on this topic are lacking, the postmenopausal women. Methods and resultsIn this retrospective study, participants were recruited from women aged 49–65 years who underwent an ultrasonography evaluation of the carotid arteries between years 2008–2012. The study included 413 subjects with serum calcium level available, without symptomatic cardiovascular disease. A physical examination, including the evaluation of body mass index, waist and hip circumferences and the blood pressure, as well as, a collection of a venous blood sample was performed. The mean age was 56 ± 7 years. The prevalence of the carotid atherosclerosis was 50.8%. The comparison between women with and without carotid atherosclerosis showed differences for the classical risk factors and for serum calcium levels (p = 0.001). The logistic regression analysis, adjusting for these risk factors, confirmed the association between serum calcium levels and carotid atherosclerosis (p = 0.011). Furthermore, we showed an increasing prevalence of carotid atherosclerosis from lower to higher calcium quartiles (p = 0.016). ConclusionWe found a positive relation between serum calcium levels and the carotid atherosclerosis in postmenopausal women. This study may suggest a redetermination of the reference range of calcemia, at least in menopause.

Hair Tissue Mineral Analysis and Metabolic Syndrome

Deficiency of minerals causes functional abnormality of enzymes, frequently resulting in metabolic disturbance. We investigated possible relationship between minerals and metabolic syndrome by analysis of hair tissue minerals. We selected 848 subjects older than 20 years of age at Ajou University Hospital from May 2004 to February 2007. We excluded the subjects who had cancers, steroid and thyroid medication, and incomplete record from the study. Finally, 343 subjects were eligible. We performed cross-sectional analysis for the relationship between minerals and metabolic syndrome. The contents of calcium, magnesium, and copper in the metabolic syndrome group were significantly lower than those of the normal group, whereas the amounts of sodium, potassium, and mercury in the metabolic syndrome group were significantly higher than those of the normal group. By dividing the subjects into quartile with the level of calcium, magnesium, and mercury concentrations, we carried out logistic regression analysis to study the subjects and found that the subjects in the third quartile of calcium and magnesium concentrations had significantly lower odds ratio (OR) of the metabolic syndrome compared with that of the lowest quartile group [OR = 0.30, confidence interval (CI) = 0.10-0.89; OR = 0.189, CI = 0.063-0.566] and that the subjects in the highest mercury quartile had significantly higher OR of the metabolic syndrome compared with that of the lowest mercury quartile group (OR = 7.35, CI = 1.73-31.1). As part of the metabolic syndrome, the optimal calcium and magnesium concentrations in hair tissue may reflect decreased risk of metabolic syndrome, whereas high mercury concentration in hair tissue may indicate increased risk of metabolic syndrome.

Proteins, Dietary Acid Load, and Calcium and Risk of Postmenopausal Fractures in the E3N French Women Prospective Study

Excess dietary proteins and "acid ash" diets have been suspected to increase the risk of osteoporosis, but experimental and epidemiological evidence is mixed. We aimed to determine whether the association between protein intake and the overall acid-base equilibrium of the diet (as renal net acid excretion [RNAE] estimate) and fracture risk vary according to calcium intake. During an average of 8.37 +/- 1.73 yr of follow-up, 2408 women reported a fracture (excluding high-impact trauma) among 36,217 postmenopausal women from the E3N prospective study. We used Cox regression models to study the interaction between calcium and, respectively, proteins and RNAE, from the 1993 dietary questionnaire for fracture risk determination, adjusting for potential confounders. There was no overall association between fracture risk and total protein or RNAE. However, in the lowest quartile of calcium (<400 mg/1000 kcal), high protein intake was associated with a significant increased fracture risk (RR = 1.51 for highest versus lowest quartile; 95% CI, 1.17-1.94). An increasing fracture risk with increasing animal protein intake was also observed (trend, p < 0.0001). A similar pattern of interaction for fracture risk was observed between RNAE and calcium. In this Western population of postmenopausal women with normal to high protein intake and fairly high calcium intake, there was no overall association between total protein or RNAE and fracture risk. However, there was some evidence that high protein-high acid ash diets were associated with an increased risk of fracture when calcium intake was low (<400 mg/1000 kcal).

Validation of a Food Frequency Questionnaire for Assessment of Calcium and Bone-Related Nutrient Intake in Rural Populations

Objective To assess the ability of a semiquantitative food frequency questionnaire (FFQ) to measure calcium and bone-related nutrient intakes in a rural South Dakota population. Design Intake estimates from FFQ were compared with four 24-hour recalls obtained quarterly during the preceding year. Subjects Convenience sample of 100 participants of the South Dakota Rural Bone Health Study were recruited, with 81 completing the FFQ. Main outcome measures Calcium and bone-related nutrient intakes were expressed as milligrams per day, milligrams per 1,000 kcal, or quartiles. Statistical analyses performed Intakes by FFQ and 24-hour recalls were compared using paired t test and quartiles were formed to examine cross-classification. Results Calcium intakes from FFQ and recalls were 1,287 and 1,141 mg/day ( P=0.01), but calcium per 1,000 kcal did not differ. Calcium intake by FFQ correlated with intake by recall when expressed as milligrams per day ( r=0.49, P<0.001) or milligrams per 1,000 kcal ( r=0.59, P<0.001). Bland-Altman graphs indicated fairly good agreement between methods. Seventy-eight percent of subjects fell into the same or within one quartile category when calcium intake was expressed as milligrams per day and 83% when expressed as milligrams per 1,000 kcal. Gross misclassification occurred in 0% to 4% of the nutrients. Conclusions Although FFQ may not be a valid indicator of an individual’s intake, it does adequately classify rural populations into quartiles of calcium and bone-related nutrient intakes, making it a useful tool for assessing dietary calcium and bone related intake in rural populations.